The main objective of this project is to study the mechanism of chemical carinogenesis by employing the technique of quantitative two-dimensional gel electrophoresis of total cellular protein. Since this technique allows for the simultaneous separation of total cellular polypeptides on a single polyacrylamide gel, it is possible to follow changes in the rate of synthesis of individual proteins as well as qualitative changes in the protein patterns as the cell undergoes malignant transformation. Our aim is to identify and characterize those proteins that are associated with the transformed phenotype. We have acquired, and have significantly revised, a computer-based system to automatically analyze autoradiograms produced from these gels. We have also been successful in analyzing silver-stained gels. This system automatically finds and measures the intensity of any polypeptide resolved by these electrophoretograms. Newly developed programs automatically match together the spot patterns found in different gels. Still other programs link together a series of gels which may constitute an experiment, allowing the investigator to quantitatively follow the synthesis of any resolvable protein through that experiment, or series of experiments. The investigator may specify various parameters and ask the computer to list those spots whose pattern of synthesis may lie within or without those parameters. Finally, several sophisticated computer-graphics programs allow the investigator to visually compare and follow various polypeptides which may be matched on a virtually unlimited number of electrophoretograms. The ultimate aim of this facility is to develop a gel analysis system that is as completely automatic as possible in analyzing the gels involved in an experiment.